Firstly the obvious point that the US felt that India was considering such a move. This could be a disasterous scenario given the history of the Kashmir region and the fact that the two countries are both nuclear powers.

Secondly, that the US did not consider that a strike on Iraq without UN approval might be used in this way. Consider the end of 2001 and start of 2002. There was widespread international support for the US, at the start of 2003, the US stands alone - something was mishandled badly for that support to wither away in quite the way it did. Exactly what happened is a question for future historians.